Patterns in ionisation energy

-Atomic radius increases

-Shielding by inner electrons increase

-less energy is used to remove the electron

-Atomic radius decreases

-Nuclear charges increase

-Shielding remains constant

-More energy required to remove an electron

-Group 3 have an s2 p1 arrangement

-Outer p1 electron is further from the nucleus

-Inner s2 electrons increase shielding so less energy is required to ionise the outer p1 electron.

-Group 6 have electron repulsion